Grinding and polishing apparatus

Abstract

A grinding and polishing apparatus wherein an air grinder is incorporated in the tool attaching spindle of a machining center main body in exactly the same manner as in the other exchange tools so that grinding and polishing operations can be performed. The tool attaching spindle is centrally formed with a tool mounting bore and a compressed air feed passage. The air grinder is attached to the tool mounting bore and driven by fluid being fed from the compressed air feed passage. The apparatus further includes air feed control means, whereby supply of fluid to the compressed air feed passage is started after the base portion of the air grinder is mounted in the tool mounting bore and supply of fluid is stopped immediately before the air grinder is removed from the tool mounting bore.

What is claimed is: 
     
       1. A grinding and polishing apparatus comprising a machining center main body,   a tool attaching spindle secured to said machining center main body and having a tool mounting bore in the middle and a passage communicating with said tool mounting bore for feeding compressed air to drive an air grinder,   said air grinder having a base portion shaped to fit in said tool mounting bore and to be thereby attached to the latter and adapted to be driven by fluid being fed from said compressed air feed passage, and   air feed control means for starting supply of fluid to said compressed air feed passage after the base portion of said air grinder is fitted in said tool attaching bore and stopping said supply of fluid immediately before the air grinder is removed from said tool mounting bore.   
     
     
       2. A grinding and polishing apparatus as set forth in claim 1, including a drive control device adapted to selectively determine whether machining is to be performed by the rotation of the air grinder alone with the rotation of said tool attaching spindle stopped or by the resultant of the rotations of said air grinder and tool attaching spindle, and give instructions concerning such selection to said machining center main body. 
     
     
       3. A grinding and polishing apparatus as set forth in claim 1, including a feed speed control device which comprises detecting means for detecting the rotative speed of the air grinder spindle during operation,   memory means for storing a reference rotative speed,   comparing means for comparing the rotative speed of the spindle detected by said detecting means with the reference rotative speed and emitting a signal on the basis of the result of the comparison, and   control means for controlling the feed speed of the tool attaching spindle of the machining center main body on the basis of the signal from said comparing means.